Charles Ellicott Commentary Leviticus 20:3

"I also will set my face against that man, and will cut him off from among his people; because he hath given of his seed unto Molech, to defile my sanctuary, and to profane my holy name." — Leviticus 20:3 (ASV)

And I will set my face against that man. —That is, make him feel my anger. (See Leviticus 17:10.)

And will cut him off. —As the preceding verse describes the offender as having been stoned to death by the people, the declaration on God’s part that He will cut off the sinner has caused some difficulty. Therefore, some understand it simply to express the same thing—that the judicial execution is God’s way of cutting off the sinner from his people. According to the administrators of the law during the Second Temple, however, the legislator assumes a case where the man has actually been guilty of the crime, and there has not been a sufficient amount of evidence to convict him. In that case, God Himself would intervene and cut the offender off. This is more in accordance with what follows.

To defile my sanctuary. —By sinning, the Israelites contracted defilement, and they defiled the sanctuary which was among them. (Leviticus 16:16.) These very people, moreover, when they had sacrificed their children to Molech, afterwards came to the sanctuary to worship God (Jeremiah 7:9–10; Ezekiel 23:37–39).

Profane my holy name. —See Leviticus 18:21.